The Oregon Alzheimer's Disease Center Biomarkers and Genetics Core was established in order to promote research utilizing genetic, plasma, and cerebrospinal fluid biomarkers of Alzheimer's disease and relevant mechanisms. The Specific Aims are: 1) To obtain and make available for research, biomarker specimens (DNA. plasma, and CSF) from OADC subjects, including healthy control subjects, subjects with mild cognitive impairment (MCI), and subjects with AD and other demenfias. 2) To obtain and make available for research, biomarker data on OADC subjects. This will include: a) apolipoprotein E (APOE) genotype on all subjects, b) single nucleotide polymorphism (SNP) profiles on select aging cohorts, and c) CSF Ap42, tau, BDNF, and F2-isoprostanes on select cohorts, d) plasma biomarker data on select cohorts. 3) To foster collaborative research involving genetics and other biomarkers emphasizing the research focus of the OADC. Research themes supported by the Core include 1) Identification of genetic predictors of both healthy brain aging and neurodegenerative dementia;2) Identification and validation of CSF and plasma biomarkers of neurodegeneration and mechanisms of neurodegeneration suitable for identification of high risk subjects, for identification of target mechanisms, and for use as outcome measures in clinical trials;3) Identification of CSF and plasma biomarkers of environmental predictors of both healthy brain aging and neurodegenerafive dementia. The Core maintains specimen banks and provides samples to qualified investigators with appropriate IRB approvals. Clinical and other data is also made available to invesfigators within HIPAA guidelines and according to local IRB regulations.